BUG: Unable to evaluate expression because the code is optimized or a native frame is on top of the call stack.

Solution:

Dont keep Server.Transfer or Request.Response inside try block.
try
{
    Server.Transfer("RoleProfile.aspx?RoleId=" + _duplicateRoleId + "&Source=CheckDup");
}


1. Either Remove Try block
2. Or use some thing like Response.Redirect("Default.aspx", false);